The short answer for a giant breed
A young Flemish Giant eats almost without limit, an adult Flemish Giant eats measured meals built around grass hay, and a senior Flemish Giant eats for weight maintenance with easier access to every bite. The pattern underneath all three stages stays the same — hay available around the clock — but the rich growth foods that build a youngster will quietly fatten an adult, and an older giant who starts leaving food needs the ration rethought rather than simply reduced. Adjust gradually at each transition, watching body condition over the ribs and spine rather than trusting the scoop alone.
Young Flemish Giants: feeding a frame that will not stop growing
A young Flemish Giant is building one of the largest rabbit frames there is, so alfalfa hay and alfalfa-based pellets are offered freely through the early months. Alfalfa's extra protein and calcium suit a growing giant in a way they would burden an adult. Youngsters graze in many small bouts across the day rather than sitting down to set meals, so the practical pattern is topped-up hay racks morning and evening, a pellet bowl that rarely empties, and fresh water checked twice daily because a growing giant drinks a great deal. Leafy greens are introduced one at a time in small amounts once the youngster is settled, so any soft droppings can be traced to the new green rather than guessed at.
Adult Flemish Giants: measured food, unlimited hay
An adult Flemish Giant moves onto unlimited grass hay — timothy, orchard, or meadow — which becomes the bulk of everything he eats and keeps his teeth and gut working. Pellets shrink to a measured daily portion scaled to his considerable size, roughly an eggcup-style measure per kilogram of body weight as a starting guide, adjusted by whether you can feel his ribs under a light layer of covering. Greens become a generous daily salad of several leafy types, and rich treats stay rare, because a Flemish Giant who stops growing but keeps eating like a youngster gains weight that his joints then have to carry. Two feeding times a day, morning and evening, suit most households and let you confirm he is eating eagerly at both.
Senior Flemish Giants: holding weight with less effort
A senior Flemish Giant often eats less enthusiastically as arthritis, dental wear, and a slower gut take their toll. Hay stays unlimited, but racks and litter trays with hay at floor level help a stiff giant who no longer stretches up comfortably. Pellets may need a modest increase or a switch to a senior formulation if weight is slipping, while an overweight senior needs the opposite — pellets trimmed and greens filling the gap. Offer meals in a quiet spot away from younger, pushier rabbits, and weigh monthly, because gradual weight loss in a senior Flemish Giant is easy to miss under a thick coat until it is well advanced.
Adjusting at each stage without upsetting the gut
Every transition for a Flemish Giant — alfalfa to grass hay, free pellets to measured, adult ration to senior — is made over one to two weeks, mixing increasing amounts of the new food into the old. Sudden swaps risk a gut slowdown in any rabbit, and a giant who stops eating is an emergency, not a wait-and-see. Watch droppings daily: they should stay large, round, and plentiful at every age. Contact a rabbit-savvy vet promptly if a Flemish Giant of any stage goes a day without eating, produces only tiny droppings, or loses weight despite a full bowl, since those signs can point to teeth, pain, or gut problems that feeding changes alone cannot fix. Recording each stage's ration in KinsLe Care Teams means a partner or sitter adjusts your giant's portions exactly when you planned, with completed feedings timestamped so a missed top-up is obvious the same day.